from selenium import webdriver
from selenium.webdriver.common.by import By
from time import sleep
wd = webdriver.Chrome()
#   设置隐式等待时间，轮询
wd.implicitly_wait(5)
wd.maximize_window()
wd.get("https://cn.bing.com/")
#   //label[contains(@class,'search')]
#   //label[starts-with(@class,'sear')]
#   //label[ends-with(@class,'rch')]
wd.find_element(By.XPATH,"//input[starts-with(@type,'sear')]").send_keys("a")